Matters needing attention in PCB model patch
- 2020-01-30-

With the development of the industry, the price of PCB model patch production is unfairly lowering. At present, many proofing companies, such as Jiefang, have cancelled all proofing/small batch film fees, and film fees have withdrawn from the stage of history. Use challenging prices to complete challenging tasks. This will be the price trend of the next circuit board proofing. Usually the produced PCB sample patch needs to be processed by the board manufacturer. After the proofing is completed, the technician will solder the components, and finally assemble it into the shell and package to form a complete product. So what relevant parameters and instructions need to be provided for the PCB sample patch?


Material: The first thing to explain is what kind of material is needed for the PCB. At present, FR4 is the most common, and the main material is epoxy resin peeled fiber cloth board.

Board layer: To explain the number of layers you make the PCB board. (The number of production layers of the pcb board is different, and the price will be different, and the proofing process of the pcb circuit board is similar.)

Solder mask color: There are many colors, you can also choose according to company requirements, generally green.

Silkscreen color: The color of the font and border of the silkscreen on the PCB is generally white.

Copper thickness: Generally, the copper thickness is scientifically calculated based on the current of the PCB circuit. Generally, the thicker the better, but the cost will be higher, so a reasonable balance is required.

Whether the via is covered with solder mask: Over solder mask is to insulate the via, otherwise it is to make the via uninsulated.

Surface coating: spray tin and gold plating.

Quantity: The quantity of PCB produced should be clearly stated.

In terms of heat dissipation, the advantages of grid copper can not be generalized. If local heating will cause PCB deformation, grid copper should be used on the condition of loss of heat dissipation and preservation of PCB integrity.

The advantage of this kind of copper paving relative to paving copper is that although the surface temperature of the board has a certain increase, it is still within the scope of commercial or industrial standards, and the damage to the components is limited.

However, if the direct consequence of PCB board bending is the appearance of virtual solder joints, it may directly lead to line failure. The comparative result is to use less damage as the best, and the real heat dissipation effect should still be solid copper.

In practical applications, the copper in the middle layer is basically seldom grid-like, that is, the uneven stress caused by temperature is not as obvious as the surface layer, and solid copper with better heat dissipation effect is basically used.